lst = [12,11,5,6,7,8,9,23,15,16]
num = int(input("请输入一个数\n"))
l = 0
for i in range(10):
    num2 = lst[i]
    b = i +1
    for a in lst[i+1:]:
        if num == num2 + a :
            print(f"索引{i},索引{b}的两个数相加等于{num}")
            l = 1
        b=b+1
if l == 0 :
    print(f"该列表里没有相加等于{num}的两个数")

